Freeport to Buy Plains, McMoRan for $9 Billion

Freeport-McMoRan Copper & Gold Inc., the world’s largest publicly traded copper producer, is paying $9 billion in cash and stock for two U.S. oil and natural gas companies that will expand it into a global natural resources giant.

Investors questioned the company’s decision to get back into the oil and gas business 18 years after its operations were split between metals mining and fuel production. Freeport, based in Phoenix, fell the most in more than four years after announcing the plan to buy Plains Exploration & Production Co. and McMoRan Exploration Co.